Sunday 25 March 2007 06.12 EDT
First published on Sunday 25 March 2007 06.12 EDT

In nine weeks' time, anyone wanting to sell their house will need to provide a home information pack for prospective buyers to look at. The most important part of this as far as the government is concerned is the energy performance certificate (EPC) - a survey of the property to assess its energy efficiency and to gauge its environmental impact in terms of CO2 emissions.

European law stipulates that all houses sold in the EU must have an EPC by 2008, and the government is hoping to pre-empt this requirement, and ensure that the system for producing EPCs is running smoothly, by including it in the home information pack this summer.

Its introduction has caused consternation ever since the government firmed up its plans last year, not least because many in the property industry believe there will not be enough home inspectors to carry out the surveys. Some claim that it is an unnecessary expense as no one will be encouraged to buy - or dissuaded from buying - a property by what an EPC has to say about it.

Others, including Emma Howard Boyd - head of socially responsible investment at Jupiter and a leading light in the eco-movement - believe EPCs could be a significant step in encouraging homeowners to make their homes more energy-efficient.

Love it or loathe it, if you put your house on sale after 1 June, you will have to commission one. So what does the survey involve and what is the report like?

Peter Ambrose runs The Partnership (www.thepartnershiplimited.com), a firm that supplies home information packs, so we asked him to have his own home surveyed for an EPC. His firm will charge a flat rate of £150 for standard EPCs. The results were quite surprising, even for him.

Peter lives in a large detached, rather nice-looking 1955 home in Surrey. The survey was very quick - about 40 minutes - but that was long enough for the inspector to find plenty that displeased him.

'We got an energy efficiency rating of 23 (out of 100), giving it an F grade,' says Peter. 'The environmental impact rating was even worse, at 21.' Individual elements that had a negative impact on the home's performance rating included the main walls, which were cavity ('very poor'), the main roof, pitched with 50mm loft insulation ('poor'), the windows, single glazed ('very poor'), and lighting, standard only ('very poor').

The report then went on to suggest how the Ambroses could improve their home performance ratings. These started with measures costing up to £500, including replacing all non-low-energy lightbulbs, insulating the hot water cylinder with a 160mm jacket, filling the main walls with blown fibre and upgrading loft insulation to 250mm. (The survey includes helpful tips such as 'always wear gloves and a mask' when handling loft insulation, and when installing a cylinder thermostat 'ask a competent plumber or heating engineer to install one'.)

These lower-cost changes would save them an estimated £322 a year in energy bills. However, none of these changes could drag the home into a higher banding. A more expensive measure would be to install an A-rated boiler with programmer, at a cost of £800-£1,000, producing a saving of another £210 a year and lifting the house into the E band for energy efficiency.

Even if the Ambroses carried out all the most expensive recommendations - internal insulation for non-cavity walls, double glazing, solar water heating and a photovoltaic system - suggested by the home inspector, they would save a total of £930 a year in energy bills, but still only achieve a D rating.

So will they be following the advice of the home inspector? 'We have replaced the oil boiler - inefficient and expensive - with a fuel-efficient gas boiler. We've already done the lagging - we've just replaced the cylinder with a new one, which will be lagged.

'But the lightbulbs are tricky, because we have a lot of candle-shaped ones, which are difficult to get in energy-efficient form - but if we could, we definitely would,' he adds.

And the double glazing? 'When we moved in the house had double glazing, but my wife had it removed because it detracted from the look of the property and replaced it with single glazing to fit with the look of the house,' Peter confesses. Sometimes form just has to win over function.

How can we get this house a better rating?

Up to £500:

Replace lightbulbs

Insulate hot water cylinder

Fill main walls with blown fibre

Upgrade loft insulation

Energy saving: £322 a year

Overall rating: F

£800-£1,000:

Install A-rated boiler with programmer

Energy saving: £210 a year

Overall rating: E

Over £1,000:

Insulate non-cavity walls

Double glazing

Solar water heating

Photovoltaic system

Energy saving: £398 a year

Overall rating: D

Win a free EPC

Specialist home information pack firm the Partnership (www.thepartnershiplimited.com), in association with Now Surveys (www.now-survey.com), is offering five free energy performance certificates on properties in England and Wales, worth £150 each, to Observer readers.